Alacranite Reference Libraries
Orpiment is a common monoclinic crystalline mineral - Chemical Composition: As2S3, arsenic trisulfide - Molecular Weight: 246.04 gm - Hardness: 1.5-2 - Optical refractive index: Biaxial (-), a=2.4, b=2.81, g=3.02 Orpiment is a mineral that is found world-wide, and occurs as a sublimation product in volcanic fumaroles, low temperature hydrothermal veins, hot springs and as a...
Realgar is a mineral of arsenic sulfide, AsS. Realgar, orpiment, and arsenopyrite provide nearly all the world's supply of arsenic as a byproduct of smelting concentrates derived from these ores.
- In the month which preceded the present; in the last month, as distinguished from the current or present month and all others.